Target marking device

ABSTRACT

A target marking device comprising a parachute or panel soaked in a chemiluminescent agent sealed inside a canister which upon rupture releases the canopy which falls to the target location where the agent reacts with oxygen in the air forming a glow visible from all quadrants, particularly at night.

tates P tent [191 [11] 3 745 324 Sheer et a1. July 16, 1973 TARGET MARKING DEVICE 3,038,407 6/1962 Robertson et al. 102 35.4 x Inventors: y y Shefler, China Lake; Harold 3,104,612 9/1963 Knacke et al. 343/18 8 X S. Duff, Ridgecrest, both of Calif. OTHER PUBLICATIONS [73] Assignee: The United States of America as Development and Test of USDA Forest Service represented by the Secretary of the Model FSS Smokejumper Parachute. In Equip Navy, Washington, DC. ment Development Report No. 40, US. Dept. of [22] Filed, June 4 1971 Argiculture Forest Service,.lan. 1956: p. 4.

[ PP N05 152,462 Primary Examiner-Benjamin A. Borchelt Assistant Examiner-James M. l-lanley 52 us. Cl. 240/225, 244/142, 102/35.6 Sciascia and ROY Miller [51] llnt. Cl. B64d 17/00, F42b 13/38 [58] Field of Search 102/35, 35.2, 35.4, 57 AB TRA T 252/1883 CL A target marking dev ce comprising a parachnteor panel soaked in a chemiluminescent agent sealed inside hich u on ru ture releases the came [56] References Cited a E w p W which falls to the target location where the agent reacts UNITED STATES PATENTS with oxygen in the air forming a glow visible from all Beatty et a1 quadrants particularly at night 2,198,697 4/1940 Driggs 102/35.6 X 3,568,354 3/1971 Yacko 252/1883 X 3 Claims, 3 Drawing Figures Patented July 10, 1973 3,745,324

1r 1 r 1 run FIG. I.

l N VENTORS SIDNEY SHEFLER HAROLD S DUFF BY; ROY MILLER ATTORNEY TARGET MARKING DEVICE BACKGROUND OF THE INVENTION The present invention is for a nighttime target marking device.

It has been the practice in the prior art of nighttime target marking to use parachute flares, while phosphorus, or explosively disseminated chemiluminescent payloads. Parachute flares light up friendly surroundings as well as unfriendly; white phosphorus is short lived and spoils the pilots night vision; and explosively disseminated payloads fall through the foliage of bushes and trees and are lost to sight. The present invention provides a nighttime signal which falls to the top of the foliage and is. visible from all quadrants, for a long period of time.

DESCRIPTION OF THE DRAWING FIG. 1 is a side elevation of the subject invention, portions being shown in cross section taken along its longitudinal axis;

FIG. 2 is a perspective of the unleased marking canopy falling into a location area; and

FIG. 3 is a section of a portion of FIG. 1 showing an alternative form of the invention.

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION Referring now to the drawing an embodiment of subject invention is shown in FIG. 1, comprising a cylindrical canister 10, provided with scored wall as shown by numeral 111 and having an integral end wall 12, which threadedly receives a tube 14 containing a time delay and impact fuze (not shown) which is initiated by a preset timing element indicated at 16. Upon initiation, a suitable detonation within tube 14 initiates a powder charge 18 which produces gas under pressure. This structure is conventional for a disperser used for a different purpose.

The structure is modified by providing a thin walled partition 20 positioned adjacent to one end of fuze tube 14. The edges of said partition 20 are fitted against the inner walls of canister so as to form a space 24 between said partition and the end of the canister. The canister is plugged by an O-ring sealed end closure 26 retained in position by a plurality of dimples 28 which are deformed into an annular groove 30 in the closure.

A parachute 32 fabricated from nylon or other suitable material and provided with a plurality of guy lines 34 is folded into space 24. Guy lines 34 are attached to a weight 36 of predetermined size which is suitably secured to the center portion of partition 20 by cement, glue, etc. Parachute 32 comprises a fabric which is saturated with an oxyluminescent compound and guy lines 34 may likewise be soaked with the same material so as to glow upon exposure to the atmosphere. The compounds used consist essentially of one of the peraminoethylenes and others known to emit light when they come in contact with the oxygen of the atmosphere. With minor adjustment to the dispenser or container other chemiluminescent materials may be used, such as oxalic type esters described in U.S. Pat. No. 3,539,794 which issued Nov. 10, 1970.

In operation of the device, initiation of the powder charge pressurizes one side of the partition which acts as a piston pushing against the end closure 26 forcing it out of engagement with the detents, the partition continuing to move to the now open end of the canister, ejecting the parachute. The parachute falls to the target location and marks the target whether the target is under a forest canopy or in a clear area. If the target is under a canopy the parachute or panel signal will still be visible from the air as it will hang on top of the canopy or shelter which may be tree tops, weeds, etc. The signal is visible from all quadrants.

As shown in FIG. 3 if it is desired to eject a plurality of parachutes some saturated with a chemiluminescent material for nighttime marking and others with a dye compound for daytime signals, a plurality of lightweight partitions designated 20 and 22, may be installed in the canister whereby a series of such markers may be dispensed therefrom. The parachute or panel can be a banner, flag, or ribbon and still have the capability of remaining on top of an overhanging protection or shelter, and thereby mark a target. Dyes used for daytime markers usually are alizarin orange or alizarin yellow because they are more easily visible.

The chemiluminescent compounds used to soak nylon, birdseye, cotton, muslin, polypropylene and other compatible materials included the following peraminoethylenes:

tetrakis(N-pyrolidinyl)ethylene;

l ,l ,3 .3 -tetramethyl-A -bi(irnidazolidine);

1,1 ,3 ,3 -tetraethyl-A -bi(imidazolidine);

l ,l -diethyl-3 ,3 dimethyl-N- -bi(imidazolidine);

tetrakis(dimethylaminomethyleneamino )ethylene; and

tetrakis(dimethylamino)ethylene. Tetrakis(dimethylamino)ethylene was used in most of the tests because it is commercially available.

What is claimed is:

1. A target-marking device comprising:

a cylindrical canister having an integral end wall;

a rupturable fuze and gas generator tube sealingly secured to said end wall;

a cup-shaped plug closing the other end of the canister and O-ring sealed thereto;

detents deformed from the wall of the canister into the plug for retaining said plug in the canister;

a thin-walled circular partition disposed adjacent said tube being slidably movable relative to the inner surface of the canister;

a parachute provided with guying lines disposed within the space between said partition and the plug; said parachute being fabricated of a material saturated with a chemiluminescent agent;

a weight of predetermined size attached to the guying lines of said parachute and disposed within the space between said partition and the plug;

the construction of said device being such that when the gas generator tube ruptures one side of the partition is pressurized causing the partition to push against the parachute and weight forcing the end plug out of the canister and releasing the parachute and the attached weight.

2. The device in accordance with claim 1 wherein the parachute is composed of polypropylene saturated with a chemiluminescent agent selected from the group consisting of tetrakis(dimcthylamino)ethylene, tetrakis(N- pyrolidinyhethylene, 1.1 .3 ,3 -tetramethyl-A -bi (imidazolidine), 1,1 ,3,3 tetraethyI-A -bi(imidazolidine). l ,l -diethyl-3 .3 -dimethyl-A '-bi(amidaz0li- 3 4 dine), and tetrakis(dimethylaniinomethyleneamino) ments, one containing a parachute saturated with a ethylenechemiluminescent agent and the other containing a 3. The device in accordance with claim 1 including a second partition disposed between the first partition parachute coated a markmg and said plug separating the canister into two compart- 5 

2. The device in accordance with claim 1 wherein the parachute is composed of polypropylene saturated with a chemiluminescent agent selected from the group consisting of tetrakis(dimethylamino)ethylene, tetrakis(N-pyrolidinyl)ethylene, 1, 11, 3, 31 - tetramethyl - Delta 2, 2 -bi(imidazolidine), 1, 11, 3, 31 - tetraethyl - Delta 2, 2 -bi(imidazolidine), 1, 11 - diethyl - 3, 31 - dimethyl - Delta 2, 2 -bi(amidazolidine), and tetrakis(dimethylaminomethyleneamino)ethylene.
 3. The device in accordancE with claim 1 including a second partition disposed between the first partition and said plug separating the canister into two compartments, one containing a parachute saturated with a chemiluminescent agent and the other containing a parachute coated with a marking dye. 